For fixtures in the prior art, a lamp body is usually fixed on a frame by screws or rivets. However, the fixation by screws requires screws, nuts, gaskets and many other components and is tedious; furthermore, the lamp body is likely to fall off after multiple times of dismounting or mounting, thereby resulting in safety hazards. With regard to the riveting by rivets, riveting equipment and a large operation space are required for stretching and riveting, and it is difficult to dismount after riveting, so it is very inconvenient.